Problem: $ { {-2} \times \left[\begin{array}{rr}{-1} & {4} \\ {3} & {-1} \\ {-1} & {0}\end{array}\right] = {?} } $
Answer: To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{rr}{-2}\times{-1} & {-2}\times{4} \\ {-2}\times{3} & {-2}\times{-1} \\ {-2}\times{-1} & {-2}\times{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{2} & {-8} \\ {-6} & {2} \\ {2} & {0}\end{array}\right]}$